Both of these URLs will render the same results:
example.com/brands/adidas/shopby/mens
example.com/mens/shopby/adidas
These combinations are possible because there is a /brand and /mens entry point, then the layered navigation (amasty) will allow different combinations. Ideally, these 2 URLs shouldn't exist, I'd like to have only 1 version of this specific set of combinations for SEO purposes.
How do you do this?
Note: We are using Magento 1 with Amasty layered navigation
Possible solution:
By adding a "new page" in the layered navigation, I can control the canonical URL, so when bots land on example.com/brands/adidas/shopby/mens or example.com/mens/shopby/adidas, I can choose to rel canonical to example.com/brands/adidas/shopby/mens and therefore solve the problem. This will work, but it's not scaleable as it needs manual configuration and very prone to human error.